Re: [Qemu-devel] [PATCH 7/7] vfio: platform: destory mutex in error path

[Auger Eric]

Hi Li,

On 10/19/18 7:20 AM, Li Qiang wrote:
> Signed-off-by: Li Qiang <address@hidden>
> ---
>  hw/vfio/platform.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
> index ba19143..e9d9e80 100644
> --- a/hw/vfio/platform.c
> +++ b/hw/vfio/platform.c
> @@ -668,7 +668,7 @@ static void vfio_platform_realize(DeviceState *dev, Error 
> **errp)
>              error_setg(errp, "%s", gerr->message);
>              g_error_free(gerr);
>              g_free(path);
> -            return;
> +            goto out;
You must set ret to != 0 otherwise the qemu_mutex_destroy will not be
reached I think. Also this will fix the fact we are not prepending the
vfio error prefix in that case, as we should.

Besides I am unsure about the cleanup strategy in case or error in
vfio_platform_realize(). The qemu process should always exit in case of
failure in vfio_platform_realize(). Platform devices can only be
cold-plugged through the qemu CLI. Cleaning all the allocated resources
may add a substantial amount of code. For instance resources allocated
in vfio_base_device_init() are not freed either. Comprehensive free in
realize() functions may only be needed in case of hotplug I think.

Thanks

Eric
>          }
>          g_free(path);
>          vdev->compat = contents;
> @@ -691,6 +691,8 @@ out:
>          return;
>      }
>  
> +    qemu_mutex_destroy(&vdev->intp_mutex);
> +
>      if (vdev->vbasedev.name) {
>          error_prepend(errp, ERR_PREFIX, vdev->vbasedev.name);
>      } else {
>